That is why HO clarify the time allowed away from the house in their listing. Feel free to not apply if it doesn’t suit you but you are not able to judge that as unreasonable because they are cats. Cats are social creatures and each has its own personalities and needs. Not all cats are comfortable being alone.
Frankly as a HO I list 6 hrs (which I think is completely reasonable amount of time for a Sitter to get out and explore) and home by 9 pm (my pets go to bed early) and no one seems to have an issue with it. If a Sitter asked me for flexibility there I would just decline the application unless it was a rare situation (wanting to spend Thanksgiving Day with nearby family, for example - I would make some arrangements for our dog to be let out in that case).