there are a number of shops in different locales that will only rip the fabric- regardless of what you may prefer. others will only cut with scissors---then theirs some that will use a rotory cutter- it all depends on how the owner was originally taught- but you will find all 3 methods common
it does no good to get upset over a shop using one method over another-
i've certainly had horrible rotory cutter cuts---where i had to trim up to 4" to straighten up my fabric- so having to trim 1/4"-1/2" on a piece of ripped fabric is much preferred to me- i've also lost 2-3" on raggy scissor cuts from some pretty expensive shops---it all depends- i usually either ask-or look around the cutting table to see if they have a cutter or scissors laying out- so i know to ask for extra to make up for the uneven cuts- if it's torn i do not usually need to purchase extra- the fabric is straight...even if the edge needs to be trimmed.