I understand your frustration for being automatically rejected for your 2:2 but you also have to consider that 1000s of applications are sometimes received by some firms for a handful of places. The cost of going through them all is high and an initial 'filter' can be useful.
2 Options i reckon:
1) Some industry grad schemes require lower grades, you start there - you move across into MC 2/3 years down the line
2) apply to small/medium outfits that are more 'personal' and require a CV and cover letter - but you will have to demonstrate that you have the "work experience and skills that would be an asset to such companies" - which you claim.
On this last point - only based on the information you have given - I would expect a recruiter to challenge you as to why:
a) If you have 8 years of solid work background you're applying for a grad scheme and not for a more experienced position.
b) Your job was good and you built up skills and experience but you left it to do an undergrad.
All in all, the first option might be better
Hope that helps!