One reason why it might be obnoxious to some is that social responsibility and service to communities and putting clients first is in the various ethics codes of therapists (at least here in the US it is). I've seen 2 ethics codes that also expect those in the profession to do some work without compensation/volunteer. No, it's not mandated, and not everyone can; but it's strongly encouraged and expected (for those who can). This is what they commit to when they join the professional organizations.

Working one or two nights a week until 7 instead of 5 isn't revolving their life around their clients or putting the client above themselves and families or being a slave to clients. There are a good number of people who truly cannot get services due to their jobs. Some types of employers allow liberal use of leave, but others don't allow any. A construction worker can't just halt the job for 2 hours every week to go to your therapist. Most businesses in the US are small businesses and don't have extra employees to provide coverage for someone to see a therapist every week. People get fired. People just don't get services.

I don't know if some are too young to have experienced this, but in the US, people had less employment rights 20 years ago. I'ts changed a lot, but you can still get fired for taking off too much work for medical appointments. It takes 2-3 hours off work for middle of the day appointments, which is often all that is available. People just can't do this every week; many are self-employed themselves.

For me, i am one of the more fortunate ones who can work this out with my employer (make up the time). Many people don't have that luxury.

Sure, it's not as convenient. It's also not as convenient to recycle, but people have the responsibility to do it. I think I am more pro-social responsibility overall, but I think those in certain professions have more responsibilities than those in other professions. Those in the therapy professions do to, otherwise, they wouldn't put it in their ethics codes. Those in the profession have more responsibility than merely doing what they like to do. Ethics codes are not different for the self-employed than they are for those who are not.

Not only that, but those therapists who never offer any evening hours, rather than the clients, who are the ones putting more stress on others in the profession who do take responsibility.