Some did and some didn't, this happened to both the established ones and new ones bought over the Internet.

Is that a problem and will it affect their future growth?

Lack of bloom is probably tied to lack of vigor, which could just be the small size of certain plants, or they needed a bit more water/fertilizer. It doesn't mean they are sick, just either immature or a little unhappy.
Some types may bloom less or more than others by their nature as well.

Thank you for your answer. While lack of water shouldn't be a problem, especially this year, and they were being fed regularly, most of those that didn't bloom are indeed small plants.

Sounds like good care and you can expect them to grow nicely next year.