If you don't want sealants for your family that's your choice. But to compare your dentist to some fluncky at the bookstore is ridiculous. Your dentist is an educated and highly trained doctor that is looking out for the best interest of your family's dental health. Sealants were found to be benficial in maintaining a person's dental health by the American Dental Association and the FDA many years ago. They are not trying to sell you some insignificant book club membership.
I totally agree. Sealants are routine and their value has been established for years. Your OP even included $$$ in the title, so it seems that money IS the issue, even though you now say money isn't an issue. You were ready to dump your dentist for "talking you into" something so basic that probably his assistant was a little surprised that you needed to be persuaded. Perhaps she could have been a bit less assertive but I think that in her shoes I would have been thinking about your kids and how a relatively simple, inexpensive thing can go a long way towards preventing very expensive, painful dental work.
You seem very defensive in reaction to the vast majority of posters agreeing with your dentist. I don't quite understand, but hopefully you will do the best thing for your child(ren).