Nothing you see done in pet stores should be immitated at home. They can get away with housing them together because it's very temporary. Or at least it should be. Doesn't make it right, though.
BP's are very solitary animals by nature. They only ever come together in the wild to breed and that's it. Then they go their separate ways. A cagemate will only stress them out. If one gets sick (regurges or has loose stool) how will you know which one it is? And if one gets sick, it is likely to pass it on to his cagemate. They will compete for the best spots in the cage...which may make it look like they're "snuggling" but actually they are both just trying to lay in the same warm spot at the same time. And there is always the slight (but real) chance one may kill and/or eat the other.
There really isn't any good reason to house them together except for breeding purposes...and then that is only done temporarily.