In my nearly 4 years with my horse, we've only had the use of an arena for about 6 months total. Riding on grass can be a PITA - more risk of slipping while wet, can be mucky in places if you continue to follow the same track, divets in the ground ect.. but what did we all do before arenas?
I'm moving my horses in a week - the current yard has lovely big sand arenas, and I'm moving them somewhere with only a field to ride in, plus roads for hacking. Much like you, they will now be closer to home. I'd rather sacrifice the luxury of an arena so that I can see them during the week and they only live 5 min away - rather than the 45 min drive after work so that I'm rushing to get in a ride before the dark sets in.
Stop for a minute, open your mind, learn. You may not agree with what I say, I may not agree with what you say but we will both learn something new.