No offense intended, but:
ANYONE WHO DOESN'T WEAR PLATE SHOES IS AN IDIOT!
If I had to choose a "level" to not wear plate shoes, it would be the advanced travel ball...batter catchers, etc. But I still wear them. I wear plate shoes at 10U, NCAA, "A" Travel Ball, league ball, doesn't matter.
A year after being hit, yeah, it doesn't hurt. But when you take the ball of the big toe in the first inning and have to hobble around for six more innings, then it hurts. How about the catcher who steps on your foot accidentally? With plate shoes, it doesn't hurt...without, potential serious injury. Or the foul ball off the top of the foot? It hurts without plate shoes, with good plate shoes you barely feel it.
I understand the problem with cost of equipment. That is one of the biggest "drawbacks" of starting to umpire fastpitch. Consider it an investment.
Wal-Mart used to carry a "goodyear" line of shoes that have good toe protection but little else...I'm thinking they were about 45 bucks. I currently have TWO pairs of plate shoes, one for inside and one for outside.
IN SUMMARY:
Office visit to doctor, with x-rays, treatment, etc: $150
Knowledge knowing your feet are protected with good plate shoes: Priceless