Why disable copy/paste into HTML?

[caption id="" align="alignleft" width="113"] Symbol for copy & paste problem on the English Wikipedia. (Photo credit: Wikipedia)[/caption]

I believe disabling copy/paste into HTML forms to be rude and bad netiquette because it's an imposition on to the user and it provides close to no security improvement. (It's sort of like opening links in new tabs or windows: if a user wants to open a link in a new window or tab, the user will do so. It's easy enough to do it with ctrl-click, but it's so much harder to go back to the old website and close that tab.)

Personally, i make use of password assistants to generate very secure passwords and make use of password managers all the time: copying and pasting password is a very essential feature i use on the personal computer. Disabling copy/paste functionality is a tremendous extra effort: so now i have to type in 16-31 random characters twice by hand? Do you know how much time it takes me? I type it once, then i make a mistake, so start all over again, type again... The impression it gives to the user is that the HTML programmers are saying "Look, i'm so good, i even know how to disable copy/paste feature". So it really feels like it's an ego thing, and i don't need it, thanks.

And indeed this is what just happened: i had to change my password on the https://my.t-mobile.com and i had to look at the password and type it twice manually. Something must have gone wrong, because it accepted the changes, but then when i went to login again, it wouldn't let me log in with the new password, and locked my account! To unlock, they sent me a SMS messages, which i cannot read, because the phone is offline now, since i'm in Italy. And all i wanted to do was to check to make sure i had money on the card, and the credit was not expired...

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