There is something fishy here and not really sure it's arbitrage.

For the first tx you mentioned there were 43.0240199999999 ETH sent and 28.4800095603247 ETH used as fee. So the total is 71.5040295603247
For the second tx there were 4.0817743759999 ETH sent and 2.70156393471649 ETH used as fee. So the total is 6.78333831071639

ETH sent	ETH fee	TOTAL	% sent from total	% fees from total	% fee from sent
4.0817743759999	2.70156393471649	6.78333831071639	60.173534%	39.826466%	66.186018%
43.0240199999999	28.4800095603247	71.5040295603247	60.170064%	39.829936%	66.195603%

The percentages are pretty similar, don't you agree ?