I have encountered the term overwhelmingly in American businesses, but now it is a slang term used in English in other countries too. I began to hear the term in the mid-1980s both inside of IBM and elsewhere (conferences and by customers of mine) in various business functions; so it is not an IT-specific term. I remember it as a 1980s term because I have long paid attention to arcane uses of vocabulary in business, e.g., "we will solution the problem," as my favorite horrible use of English, "face time," etc.
I can assure you that the vast majority of people using the term never thought about farming processes or ICBMs. What they did grasp very quickly was the long tube-like structure which were on farms, even though they did not know how and why those tubes were used. What they did understand was that whatever was in there was separated from the rest of the environment around it. From the beginning, they accepted the concept that silos represented organizations that were inward focused, paid attention to their individual needs, wants, and political behavior with less or no regard for the needs and interests of the rest of a corporation, unless such activities affected their own team, department or division. Being "silo-centrict" (I told you I collected such horrible uses of English) is considered inappropriate behavior but is (a) practiced by everyone in business to some extent or another and (b) is assumed to govern the behavior of everyone around out. Consultants and business school professor complain about how terrible this behavior is, but they are ignored because everyone's performance appraisals are designed to optimize the performance of the individual, not of the organization as a whole. BTW--I continue also to hear this term used in government as well. However, in both the private and public sectors it is a term used by large organizations, not your neighborhood bar, dry cleaning establishment, or Apple store.
I hope this is of help, and that you have learned more than you wanted to hear. Cheers!!