I've also been scared to wash mine for that reason..since they're hemmed perfectly right now. I have kettlebells, but I wouldn't have the first idea about how to attach them so the inseam doesn't stretch.
Unless in an LCDH, be exceptionally wary. Try to avoid (again if not in an LCDH) the mainstays of fake Habanos, i.e. Monte #2, Cohiba Robusto, Cohiba Esplendidos, Editions Limitada, ANYTHING AT ALL with a glass-top box.
As a sales associate for an Orvis store, I can attest to the 'M' size being able to fit a small country inside. If I couldn't get Gokey boots for half price I would def be picking up your Thorogoods.