Vegetable oils have emerged as multifunctional lipid platforms capable of integrating carotenoid extraction, stabilisation, and delivery within a single process–product framework. This review critically analyses the transformation of agro-industrial residues into functional lipid systems, highlighting the role of edible vegetable oils (e.g., soybean, sunflower, olive, and flaxseed) as green solvents and carriers for direct food incorporation. The mechanisms governing oil-mediated carotenoid extraction are examined, emphasising the coupled interaction between lipid physicochemical properties, plant matrix structure, and processing conditions, which collectively determine extraction efficiency, oxidative stability, and bioaccessibility. Technologies such as ultrasound, microwave, and supercritical fluids, together with structuring and encapsulation strategies (e.g., high internal phase emulsions, ionic gelation, and spray drying), have demonstrated improvements in carotenoid recovery, protection, and controlled release. From a technological perspective, these systems enable the development of functional oils applicable as natural colourants, antioxidants, and partial substitutes for synthetic additives in real food matrices, supporting clean-label strategies and the valorisation of agro-industrial by-products. However, system performance remains highly dependent on matrix characteristics and processing conditions, limiting comparability across studies and industrial scalability. Therefore, carotenoid-enriched oils should be understood as dynamic and reactive systems rather than passive carriers. The lack of integration among structural design, digestive behaviour, and biological functionality represents a key limitation. Future research should prioritise mechanistic approaches and multivariate optimisation to enable the translation of these systems into practical food applications.