If a job offer is valid for 60 days based on the actual wording, is it fair

for the hiring manager to press me for an answer in regards to accepting or declining their offer after only a short time has passed since they made me the offer? I know they’re desperate to fill the position, but I’ve got other pending offers I’m considering as well. I don’t think it’s fair for them to violate their own terms on the offer letter by stating that it’s valid for 60 days and try to squeeze me for an answer so soon. Is this is a sign of a shady company if they do this? Any thoughts?