Safe to lift heavy stuff (a few pounds) from outside cosmetics display?

Ive been lifting light stuff (perfume bottles) from outside cosmetic displays at malls/stores, it's so easy with a bookbag. No one cares, they all thought I was from the company lol. But what if I were to lift something heavier, like a 5-pound lotion tub or a 5-pound milk moisturizer bottle? I don't wanna blow my cover for no reason. I've already done it with a 3-pound facial cream bottle (clay mask) but I still wonder what would happen if I were to lift something even heavier.