It is misleading to correlate the offering of a flower, during expressions related purely to bhakti, with a traditional yajna procession. Or rather ... to qualify the two in terms of comparison. The BG is a bhaktic scripture, it is not of the karmakanda. Therefore, it is more of the lay-Hindu, so to speak. If one were to go full-out traditional, however, then the yajna would surely be primordial since we would be working directly with shruti-derived ordinances. However, such processions are restricted, or rather confined, only to a select-few---understandably.
Also, I have made many posts regarding the mechanicalism of the adhiyajna facets of dharma but feel that it would be suited to restate the point once more: the lack of emotional connection during the conduction of a yajna is perfectly a-okay. And more importantly, yajna-s are not "conducted for God"---that is not how they work. Furthermore, they are not entirely for human benefit. For example, the proper utterance of the mantra-s assist in retaining the significance and meaning of shabda. This, in turn, helps the vibrations act in equilibrium with things around us. And ultimately, it directly reverberates with the maintaining of rta.
In other words, we must, as per Hindu tradition, be able to separate bhaktic lines of thought from those of the karmakanda. I only write this because I get the feeling that the two are being conflated into realms that are outside their jurisdiction. It seems, as per my observations, that the "flower verse", as I'd like to call it, has been used to justify offerings of any, although passive, kind in order to give them equal footing with elaborate yajna-s. Such conflation, in my frank opinion, seems both too hasty and haughty. Instead of blurring the lines to derive some sort of justification for the actions the devoted undertake to honor their deva-s and devi-s, it would be more productive and honest to understand what the different purposes are for the varying forms or methods for ritualistic or devotional approaches.