Non-Catholics over-pay for Catholic schools.
Not only do non-Catholics pay for them ($2,000,000,000 yr), they also have to subsidise shortfall in directed Catholic property taxes ($450,000,000 yr) & inefficiency of running two systems ($200,000,000 yr).
Despite this>
Non-Catholic parents can't vote in board elections.
Non-Catholics can't run as trustees (although Catholics can in Public schools).
and >
Catholic boards can & do also discriminate against hiring gays, trans, unmarried mothers, those living together etc.
All with non-Catholic public tax dollars.