Now why would someone want to do that? They are homeless? Guess it would be considered breaking in if they were hiding there after the store closed. Not really easy to do since the clerks are very careful and watch everything.
It sure isn't legal. I suggest a new group of friends and a new definition of excitement for you. Hang at the beach, have a slumber party for the gals, etc,..you need to occupy yourself wholesomely rather than asking questions about what will land you in jail or not honey! That is NOT the kind of attention you want.
Yes it is, by hiding you have committed a crime and if you eat or take anything you will be charged with theft. Stores have very sophisticated security detection so you run a high risk of getting caught.
Breaking and entering requires some sort of forceful entry, so that's not the crime. However, the crime would be criminal trespass, unlawful entry, and if you commit a crime while in the store (stealing something), burglary.