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I posted this as a reply [and then posted it in the wrong subthread...reposting final version here] but I thought about it more, and on the Mets/Brewers odds thing, the "win %" from ESPN is something they've been doing for years. It's all over espn.com. It's not very smart, and doesn't have to be, because nothing is riding on it.
ESPNbet.com is licensed to use the ESPN name but is otherwise separate. Since their posted odds are their business, I expect them to be a lot more...meticulous, at least. The -160/+125 odds posted imply (after removing the house edge, aka de-vigging) a 58/42 probability split. And that represents only a 4.4% hold from those probabilities, so it's not outrageous. The standard -110/-110 on even money is a 4.8% hold.
Those odds are in the confusing "American format", in which a positive number is "how much would you win (in addition to your bet amount) on a $100 bet", and the negative number is -- careful here! -- how much would you have to bet in order to win $100, again in addition to getting your bet back. There are calculators to get the equivalence, since -- especially for the negative odds -- it's not real intuitive. So a 50/50 event should be +100 each way, and of course it never is. In this case, -160 would be fair odds for a 60% chance event, and +125 would be fair for a 44.4% chance event, giving a "hold" of 4.4% (60+44.4 - 100), which honestly isn't terrible as such things go.
I think the %win thing on that screen might be from a different source than the betting odds altogether in this case; the classic 50/50 bet is generally priced at -110/-110, which works out to a 4.8% hold.
You'll note that because of the way the +/- odds work, it's really hard to instantly grasp how good/bad most odds are. (It's not "halfway between the two", for one thing.) In Europe/Asia the common format is a decimal number telling you how much you multiply your stake by, including getting the stake back, so those would be [checks online calculator] 1.63 and 2.25. The single advantage of the American system is that you can see what a fair bet should be, because one is just the negation of the other. (For two-way results.) In this case it would be +-138.5.