Likely no, but then you should probably lay off for a while!

I want things that cost more than they are worth...

It will work sometimes, but if you try it too much they will catch on...

I also commonly lift food items from Walmart... way too many blind spots in the food sections, so places you can make your own blind spot.

Lift smaller things, then sell them, or do return scams for store credit.

Cheese... lots of cheese...

Alarms yes, see posts below about looking for tags and sensors.

Book bag is a larger book sized bag with 2 handles, one on each side of the main opening. A backpack has 2 straps on the main body away from the opening that is on top. For some reason large purses and book bags look less suspicious then backpacks, since students who tend to steal more have backpacks, while more well off customers tend to have book bags.

About 400+ books in the past...

I don't do backpacks into any store, I just use a large book bag with pockets that can be closed (zipped or buttoned) to the point it looks like nothing is inside the bag (short of the bigger size). Some stores have very few employees and are super easy to take books from, some are much harder due to the number of employees.

As for technique, normally get the books you want, then plant yourself in an aisle that has less foot traffic, and look like you are reading a book... then conceal and get out...

I have lifted from both stores more times than I can count. Both are easy, just play it safe...