Why not? You can use it faster. You might not be able to use the drip technique but my acrylic is wetter than my water colour.

If those boxes arrive try to paint on the inside and see if it the acrylic works and what it looks like. If there's a difference with the cardboard you bought.
I used to paint on it a lot. Also made toys out of boxes like a garage for cars, a safe with money and a kitchen. All part of the December 5th celebration: St Nicholaas (the surprise gift you make for someone else).

By the way, I do notice a huge difference if it comes to paint, it's thinner/wetter, strange substance, fewer pigment. Red is hard to get. I tried adding the red powder I bought for colouring food. I can't tell if it has any effect.