I think 'hobby' is a fine way to describe officiating.
Some guys bowl (and spend money) every Friday, while others work games (and get a bit of money).
I think factors to not getting more new or younger guys or maintaining newer guys are several factors:
1-big upfront costs
2-the number of meetings in Spring, before and during the season - time commitment.
3-not enough training or willingness to train from old dogs
4-no perceived opportunity to work Friday in the near future (related to #3 or stubbornness of old dogs not wanting a new guy-- "I've had my same crew for x years."; good ole boy club)
Conversely though, new guys generally work exclusively youth - a lot of snaps, a lot of games (up to 9 at some locations), a lot of nonsense to deal with oftentimes and tax-free cash money (instant gratification).
Most new guys will work the last half of the MS season too and get to cut their teeth more.
If they, say, doubled pay as mentioned, would more guys come out? - maybe, but reference #3 & 4 above. I think if they doubled pay I think more new guys would stick with it and some guys would stay with it longer -- i.e. $75 isnt worth it for 3 hours of this nonsense...but $150 would be worth it for 3 hours of nonsense.
Round here, we're paid at the end of the season - so round thanksgiving you get a pretty check to go spend for holidays - but conversely some guys want the instant pay. Obviously that's local problems depending on how guys are paid.
All in all in my opinion, guys walk away primarily because dealing with nonsense on the sidelines just isnt worth the $75 (FL pay including travel). - or about $19.50/hr net of taxes.....
Last year, I tried to talk an old dog into coming out to ECO AND I could nearly guarantee only games about 10mi or less from his home. He was not old, age 50, but just couldnt keep up with the game anymore (old legs).
Round these parts, for ECO including travel is $50.
His opinion: $50, after we take away taxes, etc. For a 3 hour game it came to $13/hr...I got turned down.
Certainly ECO is different from the field but in this case it was about money.