The Torah is teaching us that if I have received something, I must recognize it, even if it is a mixed blessing. Therefore, while we don’t completely welcome the Mitzrim into our midst, we can’t reject them either.
One of the most motivating forces in our avodas Hashem is a sense of “I need to pay back.” How can I not do everything in my power to pay back the huge debt that I have to Hashem? However, this is based on my understanding of the sheer amount of good I receive. Unfortunately, we are a bit like the spoiled teenager who has everything and therefore has nothing. It is difficult for us to thank Hashem. It isn’t that we don’t have; it is that we don’t perceive it.
When I train myself to appreciate the great wealth I enjoy, I gain an automatic sense of wanting to pay back. By doing this, I enjoy my stay in this world to a much greater extent, I am grateful for what others do for me, and I have an unending sense of appreciation for all the blessings I have received from Hashem.