That "convention" is one of the only standards-compliant ways to delimit URLs. Fix your copy-and-paste mechanism.
"The characters '<' and '>' are unsafe because they are used as the delimiters around URLs in free text".
The RFC itself uses "<URL:...>" because it already uses "<...>" for BNF non-terminals, which are much more common than URLs in the RFC.
Enjoy your undeserved upvote :)