I know not if this is normal gameplay or a glitch (knowing Sims 3 it could be both simultaneously).

My sim bought a large lot and built a new house. When done, everything to be kept from the old house went into family inventory then into the new house, to be augmented with several thousand simoleons of new furniture. Then back to live mode and tell my sim to move to the new house; all goes well til the end when I get a message that due to the move some items were placed into family inventory. "Some items" = everything I had moved from the old house to the new was now back in family inventory! After a lengthy blast of unacceptable language I wasted an hour putting everything back into place ...except for the food. The refrigerator had contained a hundred or so of each garden item and a couple of dozen of each grocery store item, all were now in family inventory and I couldn't remove them. Trying to drag them to the refrigerator or my sim elicited a message they could only be "placed on a floor or terrain"; trying that I found they could only be placed one at a time ...130 tomatoes ...dropped one at a time on the patio ...where my sim would then have to pick them up, one at a time, to place back into the refrigerator! And that was just one item. Not just no but "heck" no! At that point the unacceptable language reappeared, expressing my considered opinion of the ancestry, personal habits, and mental state of all responsible for such idiotic programming. I made note of my sim's cash on hand, sold everything in family inventory, went to the store and replaced all that food, then cheated to reset my sim's funds.

If this is not a glitch, what did I do wrong? (I've experienced so much trouble moving sims and/or houses in this game that I now start a new game by purchasing the lot on which I eventually want to live, even if that means my sim lives in a one room shanty for two weeks.)

I've had this happen. Or something like it. Usually after much fiddling around with NRaas MasterController and DebugEnabler, I can get some combination of commands going that shift the items back into sims' personal inventories and then placed in bulk where I want them instead of one tomato at a time. But it is a royal pain either way.

How did you move houses? I think there are three options available (apart from simply moving them in Edit Town):

(1) After you've summoned the move window from the phone, you choose the destination house and then tick "Pack Furniture" before accepting the choice. All furniture from the old house will be transferred to the family inventory and once you'll arrive in your new house you can find them there.
(2) After you've summoned the move window, you choose the destination house and then tick "Sell Furniture" before accepting the choice. All furniture except for those that you've manually placed in the family inventory will be sold and left in the old house.
(3) You purchase a second lot first, and then move your household to the second home. I cannot remember how the command is called right now, but it is something like "move household to this lot" by clicking on the destination lot itself, not using the phone. You still own the old house then in addition to the new one and no furniture will be sold or transferred except for those items that you placed in the inventory first.

But independent of however you choose to move houses it is normal that the contents of the fridge, including prepared dishes, remain in the fridge. They will either appear magically in the fridge that is in the new house, or if there's none and you've got a fridge in your inventory the items will stay in that one. So, no, it is not normal that they all appear as separate entries in the family inventory.
If you want to go all philosophical, you can imagine the fridge to be not an inventory but a portal to some separate plane of existence, where your food is stored. All fridges you own provide access to that plane, on all lots that you own within one world. Therefore a move should not affect the food in that plane because you're just moving your own position and the position of the portal.

Only once have I moved sims to an existing furnished house. That was easy; just buy the new house, pack everything to be kept from the old house into family inventory, click on the new house and have them move there.

But usually my sims have a nice house, they've just outgrown the lot. So I go to "edit town" and move the house to a larger lot ...and my sims lose all pending opportunities and wishes. Not acceptable. Next I tried moving the sims to a cheap house, moving their nice house to the new lot, then moving the sims back to their old home on the new lot; the sims kept their wishes, but the house lost all the paintings and statuary (which had rendered every room, except one downstairs bathroom, "beautifully decorated"). Also not acceptable. Apparently Evil Alliance is incapable of creating code for the simple procedure of "move everything from this lot to that lot" without losing something.



I assumed this must be a glitch; in the past I've had no such issues. This time all the contents of the refrigerator moved with it initially, but when I moved my sim to the new house everything already moved from the old house (appliances, TV, computer, awards, workbench, etc.) to the new disappeared from the new house and was placed back into family inventory ...with the food no longer in the refrigerator. ("testingcheats..." should be "testingrepairs...", it's not cheating when you are merely trying to fix things the game has screwed up)

Lol, it does seem half our time in this game is fixing things ...or trying to decipher how to fix something.