If the ever-looming regulations ever actually take effect, juice vendors won't have a choice in the matter, and they will be relegated to selling nic free juices and flavorings.
Honestly, if a vendor does NOT sell concentrated flavorings at this point, they are already behind the times. There are enough DIYers who would be happy to buy premade flavorings that are no muss, no fuss. There will always be an eternal supply of vapers who just aren't comfortable or don't have the time to DIY, but the vendors who don't sell DIY flavor concentrates are only hurting themselves by cutting off an ever growing market segment. Considering how infinitely easier it is to mix up a batch of flavoring than it is to mix individual bottles of juice with different nic levels, pg/vg ratios, and even adding flavor shots, it would seem to be a no-brainer, at least to me. Then again, what do I know?
Don't disagree with this, and I hadn't thought about that as a way for these online juice vendors to exists after the hamma drops, assuming we can still get our hands on liquid nicotine. For me personally one of the biggest satisfactions in DIY is taking individual flavors and creating more complicated flavors. I don't even like to buy say strawberries and cream as a flavor, instead I get a bottle of strawberry and bottle of cream. I would be afraid of getting hooked on one of these vendor flavors and then they drop it on me and I am screwed. I have had pretty good luck recreating some of my favorite vendor juices using flavors that 'should' never go away.