Actually, SDOT has a pretty good security system. They have a number which you can text so you don't have to make a call on the bus, and they do fare checks on

Actually, SDOT has a pretty good security system. They have a number which you can text so you don't have to make a call on the bus, and they do fare checks on the lines where people can pay on the platforms and board at the rear. But if a passenger isn't being aggressive or intrusive, the worst they're likely to get is a summons for not having a valid fare. And put yourself in a bus driver's shoes - if someone just walks on the bus, what are you going to do about it? Best case, you cause a major delay for something that is unlikely to be prosecuted. Anyways, from a practical standpoint, I think that Seattle's transit only gets about 1/3 of its funding from fares; at the end of the day their mandate is to move people around with as little friction as possible. Also, even if there was an incentive to be strict, the 'one RFID card to rule them all' system is pretty recent; plenty of people just wave some sort of ID or the paper transfer ticket that you get from paying cash. Checking all of those carefully would mean longer delays. I guess it might sound odd, but Seattle is not what you might call an ideal city. Evading a bus fare is less criminal than plenty of petty things that the police have a stated policy of ignoring, such as actual theft, and it seems like the public transit agency makes do because it's not their job to deal with that sort of thing.