Mistwell
Crusty Old Meatwad
10 gp might be a trivial sum in your game. Compare it with magic item prizes. It is not that trivial actually... at least in our current game.
Then your current game has houseruled the treasure lists. 10gp is a trivial amount. The game assumes, after the first few levels, that 10gp should be nearly meaingless to your party. It's so meaningless that the beta rules were going to allow people to just get anything around that price for free as a hand-waive. In any published adventure beyond the first few levels, you can routinely find things worth 10gp that parties are expected to leave behind because it's simply not worth the hassle - even easily removed items like a silver fork. If it's not that way in your game, that's probably a quirk of your game and not representative of most games.
Also 5e isn't big on the concept of "minions". Unlike 4e, most things have a decent chunk of hit points in this game, and can hurt you. If you cost them their action, that's a pretty good result. Lots of first level spells are aimed at doing just that, and usually with a saving throw. If you're getting them to spend their action without a save (and they STILL might miss), that's not a bad use of a first level spell. And in practice we've found it's not that common - because they know they can choose to attack the owl that's flying by with a readied action, or they can choose to attack a party member and ignore the owl for now, and usually they will choose the later.
And if you don't allow owls to do a flyby help action...that's another houserule. I think it's a fair one, but it's not how they're written. It has a 60 flight speed, can break up it's movement with a help action like anyone else could, and "The owl doesn't provoke opportunity attacks when it flies out of an enemy's reach." So by the rules, it works fine and the only way to swat it would be to ready an action to attack it when it comes within your melee range.