My vet always advises people, as routine, that their cat may be quiet or a bit stiff the day after their vaccine.
As it challenges the immune system, to start/maintain an antibody reaction it is not surprising if there is sometimes a reaction, after all people often have a swelling and a sore arm for a while after a tetanus vaccine.
However presumably the cats who are most reactive to the vaccine(s) would be the same ones who would be worse affected by the actual disease?
Unfortunately there are very few things in life that have a real benefit where that isn't balanced by some potential cost of some description, money, cost, time, effort, health, convenience, etc.
As Lippincote said,even indoor only cats can pick up airborne or physically transferred infections from shoes, hands, clothing etc.
When I had ferrets they used to have an annual half dog dose distemper vaccine, but I don't know if a half dose would work for an adult cat, as even kittens are given full sized doses and the vaccines would presumably not be licensed to be used at half doses.
Apparently even fully grown captive lions still just get a single full size domestic cat dose for their vaccines.
I guess really you would have to do an antibody titre to be sure, but presumably it would give more protection than no dose.
Catteries usually insist on vaccines both to protect your own cat from any infection carried in by any other cat or person or in the air, and to protect the other cats from anything that your cat may be carrying, as even vaccinated cats can physically carry in pathogens or sometimes be asymptomatic carriers with symptoms which sometimes then becoming apparent if the cat's immune system is compromised by stress.
At the end of the day it is a question of balancing the risk:benefit for each individual case, bearing in mind that if over 70% of the population are vaccinated the other 30% often get away without as there is much reduced chance for a disease reserviour to build up and it is harder for individual infected cases to spread and lead to generalised infection throughout the population.
Accordingly there may be some argument, catteries aside, to gain the benefit of vaccinating cats who are not badly affected, but chancing it without vaccination for cats who are severely affected.