<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I just don't understand...why marinades seem so out of favor. </div></BLOCKQUOTE>Well, likely for several reasons though I disagree that marinades are 'out of favor'. In terms of outside cooking/barbecue they were never pervasively popular. I think many people (including many cook book authors!) realize that one has to have a better understanding of ingredients in general, potential marinade ingredients in particular, and how various ingredients interact with each other and with what is being marinated for the marinade to be successful. An understanding on timing--how long a particular item will need to be marinated for best results (differences in ingredients in the marinade and different items being marinated will have different optimum times) is another requirement.
Very thick items (roasts, large fowl) do not marinate well. Thin items can be easily overwhelmed, especially mildly flavored stuff like b/s chicken breasts, shrimp, et al., if the above understandings aren't utilized. Though brining is another way of getting some flavors into dense meats, marinating does not work well with these types of items' structures. Ribs do not marinate all that well, for example.
Lastly, rubs can foster a surface texture (depending on several factors) that many find desirable: bark.
I agree that paprika is way overused in many rub recipes. It is often the primary ingredient--or the primary ingredient after salt and sugar (another overused ingredient). But paprika, imo, defines subtle, and doen't contribute much to most rubs, especially those for long-cooked items and those that will be used on items exposed to high direct heat. Lots of sugar has a dulling effect on flavors.
The other important thing for me with rubs: When meat items ('meat' here including fowl and fish), especially, are grilled or smoked or smoked/roasted, hundreds of flavors are developed simply due to to the caramelization of the surface of the item being cooked. A well made rub, appropriately applied, can allow the taster to actually taste some cooking-created flavors that might normally go unnoticed; rubs can enhance, highlight, deepen, and provide counterpoint to the flavors created during caramelization. Because flavors from marinades and flavor brines actually get into the meat, these flavors tend to remain much as they are, they do not necessarily alter during cooking nor do they necessarily combine with other flavors to create new ones as elements within rubs can. Even most cookbook authors and barbecue 'experts' don't get this. Though, depending on the ingredient(s) and quantity applied, some flavors in rubs might remain distinctive that is not what one should be shooting for--in my opinion: I am not looking for a garlic-onion-thyme-rubbed steak to taste like a garlic-onion-thyme-rubbed steak when it comes off the grill. It better not. I'm looking for flavors to be created which will result in an overarching profile that is NOT made up of identifiable key flavors, i.e., the flavor of grilled beef, the flavor of garlic, the flavor of onion, the flavor of thyme. I'm looking for a profile composed of layers of flavors that, while subtly distinguishable, are not necessarily able to be labeled beef, garlic, onion, etc. I'm looking for more complexity than that, a broader version of beef, and new flavors made by cooking and combinations of the rub ingredients with each other and the main item--and through this complexity a greater subtlety, that is, an inability on the part of the taster to identify categorically these flavors. Well made rubs, applied appropriately can do that. If I wanted these flavors (e.g., garlic, onion, thyme) to be easily identifiable--to taste like themselves when cooking is completed (and I sometimes do)--I would marinate or flavor-brine.