Practically speaking if a parish has spent money on missals, hymn books, and Office books there may not be enough money left to buy Bibles too. Add in the cost of sacristy supplies and general maintenance of a parish, Bibles fall down the priority list.
Most Catholics wouldn’t use a Bible during Mass as everything is in the missal anyway (or printed on a sheet) and others who go to spend time before the Blessed Sacrament or to pray in church would take their own devotional reading or Bible. I’ve always been able to borrow a Bible if I’ve forgotten mine from a small supply kept in church.
Most of the Anglican churches I used to attend didn’t have Bibles in the pews either as everything was in the Prayer Book.
Lots of Catholic Bibles now come with notes and cross references. The Cathechism is bursting with biblical references. Let’s not forget either that Catholics have long been encouraged to read and study Scripture in lectio divina and, as previously mentioned, granted indulgences for the prayer reading of Scripture.