Until you are on the other end of having guests you may not realize all that really goes into having someone over. It is very important to show proper appreciation. Small acts, like stripping the bed, demonstrate ???? ???? because you are showing that you appreciate that your host(ess) has increased their work load on your behalf and you are therefore trying to alleviate some of that extra work in any small way that you can.
Remember, ???? ???? is one of the fundamentals of the ????.