Sending ETH to other doesn't always mean they are alt. They can also be friend, or from same community or even they can exchange gas fee. It's better to accuse someone as alt only once you get they used same ETH address, or same social media etc.
there is nothing wrong with that and no one will be accused of cheating just because he sent coins to another member. There is nothing wrong even in having multiple accounts as long as you don't use them to cheat or to deceive others.Also, it's not a solid proof to connect accounts but when combined with other evidences then there it may raise suspicions.
In this case, it's unlikely that they are just friends helping each other with gas fee : "too many coincidences to be just luck".
