Unintentionally Funny Part

I think you're probably judging Hull's werewolf against Chaney's more iconic Wolfman of six years later, which was and remains hugely influential on the genre. Hull's werewolf is a kind of werewolf Mr. Hyde. Or, as described in the film by the Yogami character, a satanic creature, neither man nor beast, but the worst of both.

Unlike audiences of the thirties and forties who could only watch the Universal Horror Classics in linear time, we have the advantage of riding the time machine forwards and backwards, so if you had seen Werewolf of London and then The Wolfman (both for the first time) in proper order, you would not have considered the coat and hat unusual. Once Chaney's Wolfman became the standard for all subsequent werewolf films, much of what came before seemed oddly out of place.

This thread reminds me of a terrible science fiction film of the early sixties called The Hand of Death, in which John Agar does a kind of Jekyll and Hyde rip off with his head looking like a huge, burned pumpkin. In one scene Agar pulls a trench coat and hat out of the closet and deposits the latter on top of his oversized head. Needless to say, the audience (mostly bored kids) fell on the floor.

To God There Is No Zero. I Still Exist.

spectrx: Ha ha, Bela Lugosi does exactly the same thing in 'The Ape Man', he transforms himself into an ape man, puts on his hat, cape etc. and goes out into the night for a killing spree. Hilarious!

"That mans' nuts!!! Grab 'em!"

I always assumed it was an attempt at a disguise. Consider the time and locale, 19th century foggy upper class neighborhood London. Men, especially 'gentlemen', did not go out in public without hat and top coat. Even working class wore a cap and coat and usually a scarf. In dim fogginess, lack of such would make a noticeable silhouette.
I agree this werewolf is more mentally man-like than Chaney's wolfMAN, wolfman's transformation seems to be more physically violent and perhaps equally as mentally violent. Not so much wolfman is not smart enuff to disguise, it's just more compelled to go berserk.

"Pardon me while I have a strange interlude"- Marx

Pretty much the best humorous part in Werewolf of London was at the tail end of the movie with the two room and board ladies that were drunk and eating tripe. The first lady punched and knocked out the other one which was hilarious