This is how the "Dish of the Day" works. Maybe 32Red haven't considered the REALLY high rollers, as it's true that they don't offer similar percentages for that kind of volume (5K per day). However, there ARE a number of MGS casinos that might be better suited. GNUF/Betway for example have a sliding scale depending on how many loyalty points you have earned. There is a deposit match most days, ranging from 20% to 100%. These do suit a higher depositor, and at Gold level (where I am), the 100% offers are up to £250 or £300, and lesser percentage offers cater to deposits well over £1000. If you are a real whale, you can break through to the two highest tiers, where the offers are double or more what Gold players get.
You really need to speak with Pat Harrison or Ed Ware about the lack of incentive for very high rollers, they are the ones who can do something about it, and both are members here as iGaming reps.
I am surprised you managed to wring an extra match out of CS, it's generally not a good idea for casinos to give in to players who beg aggressively for extra free chips or matches.