I don't necessarily know that you should consider this an outright deal-breaker. If you value points at $0.01 each, you're getting an extra $10 worth of value for each trip where you book two one-ways instead of a round-trip. If you rebook trips less often than every 7 or 8 trips, it may still be more valuable to take the one-way bonuses and pay the $75 fee if/when necessary.

Personally, it's very rare for me to need to change a non-flexible flight after I've booked it; in those times I do need to change it, the 24-hour OLCI free standby/$25 confirmed changes almost always cover the flexibility I need.

I encourage you to consider your overall value and costs rather than just simple fee avoidance.