For attorneys contributing an article is a way to get your name before the public and educate people on your particular area of expertise. For paralegals it is a way to gain some recognition for your hard work and knowledge. Foreign student advisors, human resources personnel and scholars can educate others on specific areas of immigration law.
Advocates can draw attention to and gain support for their cause.
Anyone who has dealt with immigration can share their experience, share with others what has worked and warn others about what has not.