I wouldn't personally grudge paying expenses when they're actually on official duties
I suppose it depends on if they are accountable for their expenses and if they are reasonable.
Airmiles Andrew? Charles using the Royal Train instead of a car?
metro.co.uk/2017/06/27/prince-charles-trip-on-royal-train-cost-taxpayers-46000-6737229/
Heir to the throne Charles travelled from Windsor to Lancashire and Yorkshire to undertake engagements in Clitheroe, Settle and Harrogate in March.
The two-day trip cost £46,038, which works out at a costly £95.32 per mile.
The Royal Family made just 14 trips on the Royal Train in 2016-2017 which each cost more than £15,000 each, totalling £288,697
If an MP did that,there'd be an outrage. But when you have ZERO accountability and you are unelected, you clearly don't have to worry about money.