How bad is it that my transactions can be seen on a public server?
Your transactions can been seen by everyone; that's the block chain technology. The scare about needing a public server to know your balance and transact is the case you want to remain anonymous. If the server knew your IP and you demanded to know how much money does 1PharM... have, you could be noted as related with it. Let alone if you sent a signed transaction, which would prove it's you. You could use Tor and avoid this.
The other downside is that in HD wallets, you'll have to send all of those addresses to the server, so it can return you their balances. This is a matter of privacy due to the connection they can make between them even if some have never transacted with each other.
Because I'm a dumbass and haven't learned how to do it and why it's important to do.
Think of this. You own a few bitcoins and transact everyday. You know how Bitcoin works, but you prefer having another party delivering your information. You don't want to verify the blocks which is the whole point of self-dependence. Instead, you trust another doing it for you.
If you sit down and overthink it, you'll realize that you have no idea how much money you have. You're trusting a third party for telling it to you. The whole cash system truly works if you're badass enough to verify it yourself.
Example in real life: You have some cash, but instead of looking up on your packet you let a stranger do that for you. By the assumption he wouldn't be able to steal them from you, would you still feel confident if you allowed that man grabbing your money and paying for your goods?
