Wasn't there a hubbub a year or so ago about a pro using an integrated motor that hid in the downtube?
Anyway, my feeling is if you don't have the power in your own legs to hang with the A group, you just don't belong there and need to ride the B group. B group riding is fun too.
There is no belonging. No medals are awarded on the club ride. If everything is a competition to you, I see your point. You may love the status you get from being able to hang with a higher level group. For me it is about folks exercising together, and how good a workout can I get. If I can ride with friends who are stronger than me without slowing them down, I see that as a huge benefit. YMMV