I live in a 99% Muslim country (Turkey) - though it is laicist, you can find very religious people just like you can find atheists here. My country's practice of Islam may be a bit relaxed in comparison to other Muslim countries but I have never seen or heard anything like this in Islam. I'm not religious myself and certainly not an expert in Islam but ask any Muslim person, I bet they would say this is completely inappropriate. Islam does not prohibit kissing, it does prohibit any and every contact with an "unnatural" desire between siblings. In that regard, it is no different from other Abrahamic religions. And this indeed gives you the right to question the nature of so much touching and all. Also, from what I know, in cultures in touch with Islam, it is not common for adult men to kiss their adult sisters that much if at all- kissing on the forehead maybe to console someone. Kissing someone on the cheek is as friendly as it goes. I believe a Muslim woman would feel exactly what you are feeling.