As per title. I very, very rarely drink, and I generally just want to buy a single of something for a rare treat, however most beers/ciders/etc are sold in multipacks.

The pricing on the shelf is usually per-pack only, yet sometimes I see random products with single cans/bottles missing, and sometimes random products will have a little section of unpackaged singles, despite not having a separate price showing.

Is it generally OK to split an unopened 4- or 6-pack, or is that as weird and inappropriate as doing the equivalent in a supermarket? What even are the rules around this?