Do you have any influence? I'd say this company needs a major education into PowerShell, automation and the future of Microsoft Windows administration. It sounds like they are clearly stuck in the past. Part of the education could be financial. You tell them it takes you X amount of time at $Y/hour to complete a task, but if PowerShell were properly enabled, you could do the same task in Z amount of time and saving them money.
Otherwise, I'd be brushing off my VBScript files.
Oh, and if you think the customer would be better off hearing this from an outside expert, I'd be happy to help.
As for the execution policy, that is fairly simple to work around. It is not intended as a security feature so simply running this as a non-administrative user will completely circumvent the policy: