People having one breed?

Everybody I know favors one horse breed and thats the only breed they own. Like we got an Arabian from a guy who gave her to us (for free) because he only owns Fox Trotters. That got me thinking because she's a full-blooded Arabian mare! Why do people tend to do that? I have many breeds of horses I wanna try and own. Paso Fino and Tennessee Walkers are my favorites because Paso Finos are "half-human" and its easy to form relationships with them because they are sensitive to your emotions. TW are beautiful and I love the way they nod their head when they walk, theyre beautiful. The gelding I have now is half TW. I like Rocky Mountains strictly because of their signature chocolate color and blonde mane and I heard they have the smoothest ride. I love Arabians because of their spirit and the way they carry themselves. Quarter Horses because they are very calm and dependable. Someone help me, do you migrate more towards one horse (what breed and why) and would it be weird if I owned different breeds of horses? I plan on using some for show, is it matters. reining.