Three reasons, the first two of which are pretty silly...
1 - I'm a remington guy who uses federal ammo with Nosler bullets almost exclusively, and have done so for the last 15+ years. Not that I'm resistant to change, but I do like being 100% familiar and comfortable with what I'm using.
2 - very little experience with the Hornady stuff - just don't know about it, and havn't built up any confidence in it. Are the interbonds as good as the accubonds? I have to admit I tried them in my 270 once and they did shoot nicely at paper anyways.. I'll have to look up moreinfo on the interbond and interlocks...
3 - Here's the only real reason.. I'm a bit of an accuracy nut, and I've had bad luck over the years finding the load my rifle likes the best. So since there's only 3 loads available, I'm nervous that all three might be duds and then what??? Of course, the 375 isn't exactly going to be a long range rig, and also might push me towrds reloading - just don't really have the time...
Cheers,
Cleo